MARKIN, M. V. On certain spectral features inherent to scalar type spectral operators. Methods of Functional Analysis and Topology, [S. l.], v. 23, n. 1, p. 60–65, 2017. Disponível em: https://zen.imath.kiev.ua/index.php/mfat/article/view/654. Acesso em: 16 dec. 2025.